An efficient electrochemical biosensor for Vitamin-D 3 detection based on aspartic acid functionalized gadolinium oxide nanorods

摘要

In this study, an efficient electrochemical biosensor for Vitamin-D3detection using gadolinium oxide nanorods (Gd2O3NRs) has been reported. Gd2O3NRs were hydrothermally synthesized and functionalized with aspartic acid (Asp-Gd2O3NRs). Asp functionalization did not change the phase, shape and structure of Gd2O3NRs. The high-resolution transmission electron microscopy study revealed the diameter of Asp-Gd2O3NRs as 14.26?±?0.13?nm with enhanced dispersivity. The Gd2O3NRs and Asp-Gd2O3NRs showed zeta potential of +29 and +24?mV, respectively. Asp-Gd2O3NRs exhibited enhanced hydrophilicity and electrochemical property than the bare Gd2O3NRs. A thin film of Asp-Gd2O3NRs was deposited on a glass substrate coated with indium-tin-oxide (ITO) by electrophoretic deposition. The immobilization of Vitamin-D3monoclonal antibody (Ab-VD) was done on the surface of Asp-Gd2O3NRs/ITO electrode for determination of Vitamin-D3. The study of BSA/Ab-VD/Asp-Gd2O3NRs/ITO immunoelectrode response with different Vitamin-D3concentration was investigated using differential pulse voltammetry technique. The results of response study exhibited an improved sensitivity value of 0.38?μA?ng?1?mL?cm?2with a linear range of 10–100?ng?mL?1for Vitamin-D3detection while the detection limit of 0.10?ng?mL?1was obtained. This immunosensor showed a satisfactory response to commercially available Vitamin-D3oral solution. Besides this,in vitrostudy of Gd2O3NRs and Asp-Gd2O3NRs was performed on RAW 264.7 and MCF-7 cells.